176 



THE UPPER EXTREMITIES. 



low, while on the back of the arm, with its largest swell- 

 ing above, is the triceps. 



Upper Arm Muscles. The biceps is the most important 

 arm muscle. It rises by a short head from the coracoid 

 process of the scapula and by a long head from a tubercle 



FIG. 71. 



FIG. 70. Superficial muscles of shoulder and arm (from before): 1, Pectoralia 

 major; 2, deltoid; 3, biceps brachii; 4, brachialis anticus; 5, triceps; 6, pronator 

 radii teres; 7, flexor carpi radialis; 8, palmaris longus; 9, flexor carpi ulnaris;10, 

 supinator longus; 11, extensor ossis metacarpi pollicis; 12, extensor brevis 

 pollicis; 13, flexor sublimis digitorum; 14, flexor longus pollicis; 15, flexor pro- 

 fundus digitorum; 16, palmaris brevis; 17, abductor pollicis. (Borland's Dic- 

 tionary.) 



FIG. 71. Superficial muscles of shoulder and arm (from behind) : 1, Trapezius; 

 2, deltoid; 3, rhomboideus major; 4, infraspinatus; 5, teres minor; 6, teres major; 

 7, latissimus dorsi; 8, triceps; 9, anconeus; 10, brachialis anticus; 11, supinator 

 longus; 12, extensor carpi radialis longior; 13, extensor carpi radialis brevior; 14, 

 extensor communis digitorum; 15, extensor carpi ulnaris; 16, flexor carpi ulnaris; 

 17, extensor ossis metacarpi pollicis; 18, extensor brevis pollicis; 19, tendon of 

 extensor longus pollicis. (Borland's Bictionary.) 



on the upper margin of the glenoicl cavity, the tendon 

 arching over the head of the humerus and descending 

 in the bicipital groove. It is inserted into the back of 

 the tuberosity of the radius and by a broad aponeurosis 

 into the fascia of the forearm. It flexes and supinates 

 the forearm and renders the fascia tense. Its inner 



